Microfluidic platforms for extracellular vesicle isolation, analysis and therapy in cancer

Extracellular vesicles (EVs) are small lipidic particles packed with proteins, DNA, messenger RNA and microRNAs of their cell of origin that act as critical players in cellâ cell communication. These vesicles have been identified as pivotal mediators in cancer progression and the formation of metastatic niches. Hence, their isolation and analysis from circulating biofluids is envisioned as the next big thing in the field of liquid biopsies for early non-invasive diagnosis and patient follow-up. Despite the promise, current benchtop isolation strategies are not compatible with point-of-care testing in a clinical setting. Microfluidic platforms are disruptive technologies capable of recovering, analyzing, and quantifying EVs within clinical samples with limited volume, in a high-throughput manner with elevated sensitivity and multiplexing capabilities. Moreover, they can also be employed for the controlled production of synthetic EVs and effective drug loading to produce EV-based therapies. In this review, we explore the use of microfluidic platforms for the isolation, characterization, and quantification of EVs in cancer, and compare these platforms with the conventional methodologies. We also highlight the state-of-the-art in microfluidic approaches for EV-based cancer therapeutics. Finally, we analyze the currently active or recently completed clinical trials involving EVs for cancer diagnosis, treatment or therapy monitoring and examine the future of EV-based point-of-care testing platforms in the clinic and EV-based therapy production by the industry.D. C. acknowledges the financial support from the Portuguese Foundation for Science and Technology (FCT) under the program CEEC Individual 2017 (CEECIND/00352/2017). C. M. A., S. C. K. and D. C. also thank the support from the FCT under the scope of the projects 2MATCH (PTDC/BTM-ORG/28070/2017) and BREAST-IT (PTDC/BTM-ORG/28168/2017) funded by the Programa Operacional Regional do Norte supported by European Regional Development Funds (ERDF). The authors also thank the financial support from the European Union Framework Program for Research and Innovation Horizon 2020 on FoReCaST project under (Grant Number: 668983). B. C. S. thanks the support from the EMBO Installation Grant 3921, the grant 2017NovPCC1058 from Breast Cancer Now's Catalyst Programme, which is supported by funding from Pfizer, the grant 765492 from H2020-MSCAITN-2017, the grant LCF/PR/HR19/52160014 from “La Caixa” Foundation and the Champalimaud Foundation